RS-tracker/imet/imet1rs_dft.c

844 wiersze
24 KiB
C

/*
* iMet-1-RS / iMet-4
* Bell202 8N1
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <complex.h>
#include <math.h>
// optional JSON "version"
// (a) set global
// gcc -DVERSION_JSN [-I<inc_dir>] ...
#ifdef VERSION_JSN
#include "version_jsn.h"
#endif
// or
// (b) set local compiler option, e.g.
// gcc -DVER_JSN_STR=\"0.0.2\" ...
typedef unsigned char ui8_t;
int option_verbose = 0, // ausfuehrliche Anzeige
option_raw = 0, // rohe Frames
option_rawbits = 0,
option_b = 1,
option_json = 0,
wavloaded = 0;
/* ------------------------------------------------------------------------------------ */
int sample_rate = 0, bits_sample = 0, channels = 0;
//float samples_per_bit = 0;
int findstr(char *buff, char *str, int pos) {
int i;
for (i = 0; i < 4; i++) {
if (buff[(pos+i)%4] != str[i]) break;
}
return i;
}
int read_wav_header(FILE *fp) {
char txt[4+1] = "\0\0\0\0";
unsigned char dat[4];
int byte, p=0;
if (fread(txt, 1, 4, fp) < 4) return -1;
if (strncmp(txt, "RIFF", 4)) return -1;
if (fread(txt, 1, 4, fp) < 4) return -1;
// pos_WAVE = 8L
if (fread(txt, 1, 4, fp) < 4) return -1;
if (strncmp(txt, "WAVE", 4)) return -1;
// pos_fmt = 12L
for ( ; ; ) {
if ( (byte=fgetc(fp)) == EOF ) return -1;
txt[p % 4] = byte;
p++; if (p==4) p=0;
if (findstr(txt, "fmt ", p) == 4) break;
}
if (fread(dat, 1, 4, fp) < 4) return -1;
if (fread(dat, 1, 2, fp) < 2) return -1;
if (fread(dat, 1, 2, fp) < 2) return -1;
channels = dat[0] + (dat[1] << 8);
if (fread(dat, 1, 4, fp) < 4) return -1;
memcpy(&sample_rate, dat, 4); //sample_rate = dat[0]|(dat[1]<<8)|(dat[2]<<16)|(dat[3]<<24);
if (fread(dat, 1, 4, fp) < 4) return -1;
if (fread(dat, 1, 2, fp) < 2) return -1;
//byte = dat[0] + (dat[1] << 8);
if (fread(dat, 1, 2, fp) < 2) return -1;
bits_sample = dat[0] + (dat[1] << 8);
// pos_dat = 36L + info
for ( ; ; ) {
if ( (byte=fgetc(fp)) == EOF ) return -1;
txt[p % 4] = byte;
p++; if (p==4) p=0;
if (findstr(txt, "data", p) == 4) break;
}
if (fread(dat, 1, 4, fp) < 4) return -1;
fprintf(stderr, "sample_rate: %d\n", sample_rate);
fprintf(stderr, "bits : %d\n", bits_sample);
fprintf(stderr, "channels : %d\n", channels);
if ((bits_sample != 8) && (bits_sample != 16) && (bits_sample != 32)) return -1;
//samples_per_bit = sample_rate/(float)BAUD_RATE;
//fprintf(stderr, "samples/bit: %.2f\n", samples_per_bit);
return 0;
}
int f32read_sample(FILE *fp, float *s) {
int i;
unsigned int word = 0;
short *b = (short*)&word;
float *f = (float*)&word;
for (i = 0; i < channels; i++) {
if (fread( &word, bits_sample/8, 1, fp) != 1) return EOF;
if (i == 0) { // i = 0: links bzw. mono
//if (bits_sample == 8) sint = b-128; // 8bit: 00..FF, centerpoint 0x80=128
//if (bits_sample == 16) sint = (short)b;
if (bits_sample == 32) {
*s = *f;
}
else {
if (bits_sample == 8) { *b -= 128; }
*s = *b/128.0;
if (bits_sample == 16) { *s /= 256.0; }
}
}
}
return 0;
}
/* ------------------------------------------------------------------------------------ */
// Bell202, 1200 baud (1200Hz/2200Hz), 8N1
#define BAUD_RATE 1200
#define BITS (10)
#define LEN_BITFRAME BAUD_RATE
#define LEN_BYTEFRAME (LEN_BITFRAME/BITS)
#define HEADLEN 30
typedef struct {
// GPS
int hour;
int min;
int sec;
float lat;
float lon;
int alt;
int sats;
float vH; float vD; float vV; // eGPS
// PTU
int frame;
float temp;
float pressure;
float humidity;
float batt;
// XDATA
char xdata[2*LEN_BYTEFRAME+1]; // xdata hex string: aux_str1#aux_str2...
char *paux;
//
int gps_valid;
int ptu_valid;
//
int jsn_freq; // freq/kHz (SDR)
} gpx_t;
gpx_t gpx;
char header[] = "1111111111111111111""10""10000000""1";
char buf[HEADLEN+1] = "x";
int bufpos = -1;
int bitpos;
ui8_t bitframe[LEN_BITFRAME+1] = { 0, 1, 0, 0, 0, 0, 0, 0, 0, 1};
ui8_t byteframe[LEN_BYTEFRAME+1];
int N, ptr;
float *buffer = NULL;
/* ------------------------------------------------------------------------------------ */
void inc_bufpos() {
bufpos = (bufpos+1) % HEADLEN;
}
int compare() {
int i=0, j = bufpos;
while (i < HEADLEN) {
if (j < 0) j = HEADLEN-1;
if (buf[j] != header[HEADLEN-1-i]) break;
j--;
i++;
}
return i;
}
int bits2byte(ui8_t *bits) {
int i, d = 1, byte = 0;
if ( bits[0]+bits[1]+bits[2]+bits[3]+bits[4] // 1 11111111 1 (sync)
+bits[5]+bits[6]+bits[7]+bits[8]+bits[9] == 10 ) return 0xFFFF;
for (i = 1; i < BITS-1; i++) { // little endian
if (bits[i] == 1) byte += d;
else if (bits[i] == 0) byte += 0;
d <<= 1;
}
return byte & 0xFF;
}
int bits2bytes(ui8_t *bits, ui8_t *bytes, int len) {
int i;
int byte;
for (i = 0; i < len; i++) {
byte = bits2byte(bits+BITS*i);
bytes[i] = byte & 0xFF;
if (byte == 0xFFFF) break;
}
return i;
}
void print_rawbits(int len) {
int i;
for (i = 0; i < len; i++) {
if ((i % BITS == 1) || (i % BITS == BITS-1)) fprintf(stdout, " ");
fprintf(stdout, "%d", bitframe[i]);
}
fprintf(stdout, "\n");
}
/* -------------------------------------------------------------------------- */
int crc16poly = 0x1021; // CRC16-CCITT
int crc16(ui8_t bytes[], int len) {
int rem = 0x1D0F; // initial value
int i, j;
for (i = 0; i < len; i++) {
rem = rem ^ (bytes[i] << 8);
for (j = 0; j < 8; j++) {
if (rem & 0x8000) {
rem = (rem << 1) ^ crc16poly;
}
else {
rem = (rem << 1);
}
rem &= 0xFFFF;
}
}
return rem;
}
/* -------------------------------------------------------------------------- */
#define LEN_GPSePTU (18+20)
/*
standard frame:
01 02 (GPS) .. .. 01 04 (ePTU) .. ..
*/
#define SOH_01 0x01
#define PKT_PTU 0x01
#define PKT_GPS 0x02
#define PKT_XDATA 0x03
#define PKT_ePTU 0x04
#define PKT_eGPS 0x05
/*
PTU (enhanced) Data Packet (LSB)
offset bytes description
0 1 SOH = 0x01
1 1 PKT_ID = 0x01/0x04
2 2 PKT = packet number
4 3 P, mbs (P = n/100)
7 2 T, °C (T = n/100)
9 2 U, % (U = n/100)
11 1 Vbat, V (V = n/10)
12 2 Tint, °C (Tint = n/100)
14 2 Tpr, °C (Tpr = n/100)
16 2 Tu, °C (Tu = n/100)
12/18 2 CRC (16-bit)
packet size = 14/20 bytes
*/
#define pos_PCKnum 0x02 // 2 byte
#define pos_PTUprs 0x04 // 3 byte
#define pos_PTUtem 0x07 // 2 byte int
#define pos_PTUhum 0x09 // 2 byte
#define pos_PTUbat 0x0B // 1 byte
#define pos_PTUcrc 0x0C // 2 byte
#define pos_ePTUtint 0x0C // 2 byte
#define pos_ePTUtpr 0x0E // 2 byte
#define pos_ePTUtu 0x10 // 2 byte
#define pos_ePTUcrc 0x12 // 2 byte
int print_ePTU(int pos, ui8_t PKT_ID) {
int P, U;
short T;
int bat, pcknum;
int crc_val, crc; // 0x04: ePTU 0x01: PTU
int posPTUCRC = (PKT_ID == PKT_ePTU) ? pos_ePTUcrc : pos_PTUcrc;
if (PKT_ID != PKT_ePTU && PKT_ID != PKT_PTU) return -1;
crc_val = ((byteframe+pos)[posPTUCRC] << 8) | (byteframe+pos)[posPTUCRC+1];
crc = crc16(byteframe+pos, posPTUCRC); // len=pos
P = (byteframe+pos)[pos_PTUprs] | ((byteframe+pos)[pos_PTUprs+1]<<8) | ((byteframe+pos)[pos_PTUprs+2]<<16);
T = (byteframe+pos)[pos_PTUtem] | ((byteframe+pos)[pos_PTUtem+1]<<8);
U = (byteframe+pos)[pos_PTUhum] | ((byteframe+pos)[pos_PTUhum+1]<<8);
bat = (byteframe+pos)[pos_PTUbat];
pcknum = (byteframe+pos)[pos_PCKnum] | ((byteframe+pos)[pos_PCKnum+1]<<8);
fprintf(stdout, "[%d] ", pcknum);
fprintf(stdout, " P:%.2fmb ", P/100.0);
fprintf(stdout, " T:%.2f°C ", T/100.0);
fprintf(stdout, " U:%.2f%% ", U/100.0);
fprintf(stdout, " bat:%.1fV ", bat/10.0);
fprintf(stdout, " # ");
fprintf(stdout, " CRC: %04X ", crc_val);
fprintf(stdout, "- %04X ", crc);
if (crc_val == crc) {
fprintf(stdout, "[OK]");
gpx.ptu_valid = PKT_ID;
gpx.frame = pcknum;
gpx.pressure = P/100.0;
gpx.temp = T/100.0;
gpx.humidity = U/100.0;
gpx.batt = bat/10.0;
}
else {
fprintf(stdout, "[NO]");
gpx.ptu_valid = 0;
}
fprintf(stdout, "\n");
return (crc_val != crc);
}
/*
GPS (enhanced) Data Packet (LSB)
offset bytes description
0 1 SOH = 0x01
1 1 PKT_ID = 0x02/0x05
2 4 Latitude, +/- deg (float)
6 4 Longitude, +/- deg (float)
10 2 Altitude, meters (Alt = n-5000)
12 1 nSat (0 - 12)
13 4 velE m/s (float)
17 4 velN m/s (float)
21 4 velU m/s (float)
13/25 3 Time (hr,min,sec)
16/28 2 CRC (16-bit)
packet size = 18/30 bytes
*/
#define pos_GPSlat 0x02 // 4 byte float
#define pos_GPSlon 0x06 // 4 byte float
#define pos_GPSalt 0x0A // 2 byte int
#define pos_GPSsats 0x0C // 1 byte
#define pos_GPStim 0x0D // 3 byte
#define pos_GPScrc 0x10 // 2 byte
#define pos_eGPSvE 0x0D // 4 byte float
#define pos_eGPSvN 0x11 // 4 byte float
#define pos_eGPSvU 0x15 // 4 byte float
#define pos_eGPStim 0x19 // 3 byte
#define pos_eGPScrc 0x1C // 2 byte
int print_eGPS(int pos, ui8_t PKT_ID) {
float lat, lon;
float vE, vN, vU, vH, vD; // E,N,U, speed, dir/heading
int alt, sats;
int std, min, sek;
int crc_val, crc; // 0x02: GPS 0x05: eGPS
int posGPStim = (PKT_ID == PKT_GPS) ? pos_GPStim : pos_eGPStim;
int posGPSCRC = (PKT_ID == PKT_GPS) ? pos_GPScrc : pos_eGPScrc;
if (PKT_ID != PKT_GPS && PKT_ID != PKT_eGPS) return -1;
crc_val = ((byteframe+pos)[pos_GPScrc] << 8) | (byteframe+pos)[pos_GPScrc+1];
crc = crc16(byteframe+pos, pos_GPScrc); // len=pos
//lat = *(float*)(byteframe+pos+pos_GPSlat);
//lon = *(float*)(byteframe+pos+pos_GPSlon);
// //raspi: copy into (aligned) float
memcpy(&lat, byteframe+pos+pos_GPSlat, 4);
memcpy(&lon, byteframe+pos+pos_GPSlon, 4);
alt = ((byteframe+pos)[pos_GPSalt+1]<<8)+(byteframe+pos)[pos_GPSalt] - 5000;
sats = (byteframe+pos)[pos_GPSsats];
std = (byteframe+pos)[posGPStim+0];
min = (byteframe+pos)[posGPStim+1];
sek = (byteframe+pos)[posGPStim+2];
fprintf(stdout, "(%02d:%02d:%02d) ", std, min, sek);
fprintf(stdout, " lat: %.6f° ", lat);
fprintf(stdout, " lon: %.6f° ", lon);
fprintf(stdout, " alt: %dm ", alt);
fprintf(stdout, " sats: %d ", sats);
gpx.vH = gpx.vD = gpx.vV = 0;
if (PKT_ID == PKT_eGPS) {
memcpy(&vE, byteframe+pos+pos_eGPSvE, 4);
memcpy(&vN, byteframe+pos+pos_eGPSvN, 4);
memcpy(&vU, byteframe+pos+pos_eGPSvU, 4);
vH = sqrt(vE*vE+vN*vN);
vD = atan2(vE, vN) * 180.0 / M_PI;
if (vD < 0) vD += 360.0;
// TODO: TEST eGPS/vel
fprintf(stdout, " vH: %.1fm/s D: %.1f° vV: %.1fm/s ", vH, vD, vU);
}
fprintf(stdout, " # ");
fprintf(stdout, " CRC: %04X ", crc_val);
fprintf(stdout, "- %04X ", crc);
if (crc_val == crc) {
fprintf(stdout, "[OK]");
gpx.gps_valid = PKT_ID;
gpx.lat = lat;
gpx.lon = lon;
gpx.alt = alt;
gpx.sats = sats;
gpx.hour = std;
gpx.min = min;
gpx.sec = sek;
if (PKT_ID == PKT_eGPS) {
gpx.vH = vH;
gpx.vD = vD;
gpx.vV = vU;
}
}
else {
fprintf(stdout, "[NO]");
gpx.gps_valid = 0;
}
fprintf(stdout, "\n");
return (crc_val != crc);
}
/*
Extra Data Packet - XDATA
offset bytes description
0 1 SOH = 0x01
1 1 PKT_ID = 0x03
2 2 N = number of data bytes to follow
3+N 2 CRC (16-bit)
N=8, ID=0x01: ECC Ozonesonde (MSB)
3 1 Instrument_type = 0x01 (ID)
4 1 Instrument_number
5 2 Icell, uA (I = n/1000)
7 2 Tpump, °C (T = n/100)
9 1 Ipump, mA
10 1 Vbat, (V = n/10)
11 2 CRC (16-bit)
packet size = 12 bytes
//
ID=0x05: OIF411
ID=0x08: CFH (Cryogenic Frost-Point Hygrometer)
ID=0x19: COBALD (Compact Optical Backscatter Aerosol Detector)
*/
int print_xdata(int pos, ui8_t N) {
ui8_t InstrumentNum;
short Tpump;
unsigned short Icell, Ipump, Vbat;
int crc_val, crc;
int crc_len = 3+N;
crc_val = ((byteframe+pos)[crc_len] << 8) | (byteframe+pos)[crc_len+1];
crc = crc16(byteframe+pos, crc_len); // len=pos
fprintf(stdout, " XDATA ");
// (byteframe+pos)[2] = N
if (N == 8 && (byteframe+pos)[3] == 0x01)
{ // Ozonesonde 01 03 08 01 .. .. (MSB)
InstrumentNum = (byteframe+pos)[4];
Icell = (byteframe+pos)[5+1] | ((byteframe+pos)[5]<<8); // MSB
Tpump = (byteframe+pos)[7+1] | ((byteframe+pos)[7]<<8); // MSB
Ipump = (byteframe+pos)[9];
Vbat = (byteframe+pos)[10];
fprintf(stdout, " Icell:%.3fuA ", Icell/1000.0);
fprintf(stdout, " Tpump:%.2f°C ", Tpump/100.0);
fprintf(stdout, " Ipump:%dmA ", Ipump);
fprintf(stdout, " Vbat:%.1fV ", Vbat/10.0);
}
else {
int j;
fprintf(stdout, " (N=0x%02X)", N);
for (j = 0; j < N; j++) fprintf(stdout, " %02X", (byteframe+pos)[3+j]);
}
if (crc_val == crc && (gpx.paux-gpx.xdata)+2*(N+1) < 2*LEN_BYTEFRAME) {
// hex(xdata[2:3+N]) , strip [0103NN]..[CRC16] , '#'-separated
int j;
if (gpx.paux > gpx.xdata) {
*(gpx.paux) = '#';
gpx.paux += 1;
}
//exclude length (byteframe+pos)[2]=N (sprintf(gpx.paux, "%02X", (byteframe+pos)[2]); gpx.paux += 2;)
for (j = 0; j < N; j++) {
sprintf(gpx.paux, "%02X", (byteframe+pos)[3+j]);
gpx.paux += 2;
}
*(gpx.paux) = '\0';
}
fprintf(stdout, " # ");
fprintf(stdout, " CRC: %04X ", crc_val);
fprintf(stdout, "- %04X ", crc);
if (crc_val == crc) {
fprintf(stdout, "[OK]");
}
else {
fprintf(stdout, "[NO]");
}
fprintf(stdout, "\n");
return (crc_val != crc);
}
/* -------------------------------------------------------------------------- */
int print_frame(int len) {
int i;
int framelen;
int crc_err1 = 0,
crc_err2 = 0,
crc_err3 = 0;
int ofs = 0;
int out = 0;
if ( len < 2 || len > LEN_BYTEFRAME) return -1;
for (i = len; i < LEN_BYTEFRAME; i++) byteframe[i] = 0;
gpx.gps_valid = 0;
gpx.ptu_valid = 0;
framelen = bits2bytes(bitframe, byteframe, len);
if (option_rawbits)
{
print_rawbits(framelen*BITS);
}
else
{
if (option_raw) {
for (i = 0; i < framelen; i++) { // LEN_GPSePTU
fprintf(stdout, "%02X ", byteframe[i]);
}
fprintf(stdout, "\n");
out |= 8;
}
//else
{
ofs = 0;
gpx.xdata[0] = '\0';
gpx.paux = gpx.xdata;
while (ofs < framelen && byteframe[ofs] == SOH_01) // SOH = 0x01
{
ui8_t PKT_ID = byteframe[ofs+1];
if (PKT_ID == PKT_GPS || PKT_ID == PKT_eGPS) // GPS/eGPS Data Packet
{
int posGPSCRC = (PKT_ID == PKT_GPS) ? pos_GPScrc : pos_eGPScrc;
crc_err1 = print_eGPS(ofs, PKT_ID); // packet offset in byteframe
ofs += posGPSCRC+2;
out |= 1;
}
else if (PKT_ID == PKT_ePTU || PKT_ID == PKT_PTU) // ePTU/PTU Data Packet
{
int posPTUCRC = (PKT_ID == PKT_ePTU) ? pos_ePTUcrc : pos_PTUcrc;
crc_err2 = print_ePTU(ofs, PKT_ID); // packet offset in byteframe
ofs += posPTUCRC+2;
out |= 2;
}
else if (PKT_ID == PKT_XDATA) // Extra Data Packet
{
ui8_t N = byteframe[ofs+2];
if (N > 0 && ofs+2+N+2 < framelen)
{
crc_err3 = print_xdata(ofs, N); // packet offset in byteframe
ofs += N+3+2;
out |= 4;
}
else {
break;
}
}
else {
break;
}
}
// if (crc_err1==0 && crc_err2==0) { }
if (option_json) {
if (gpx.gps_valid && gpx.ptu_valid) // frameNb part of PTU-pck
{
char *ver_jsn = NULL;
fprintf(stdout, "{ \"type\": \"%s\"", "IMET");
fprintf(stdout, ", \"frame\": %d, \"id\": \"iMet\", \"datetime\": \"%02d:%02d:%02dZ\", \"lat\": %.5f, \"lon\": %.5f, \"alt\": %d, \"sats\": %d, \"temp\": %.2f, \"humidity\": %.2f, \"pressure\": %.2f, \"batt\": %.1f",
gpx.frame, gpx.hour, gpx.min, gpx.sec, gpx.lat, gpx.lon, gpx.alt, gpx.sats, gpx.temp, gpx.humidity, gpx.pressure, gpx.batt);
// TODO: TEST eGPS/vel
if (0 && gpx.gps_valid == PKT_eGPS) {
fprintf(stdout, ", \"vel_h\": %.5f, \"heading\": %.5f, \"vel_v\": %.5f", gpx.vH, gpx.vD, gpx.vV );
}
if (gpx.xdata[0]) {
fprintf(stdout, ", \"aux\": \"%s\"", gpx.xdata );
}
if (gpx.jsn_freq > 0) {
fprintf(stdout, ", \"freq\": %d", gpx.jsn_freq );
}
// Reference time/position
fprintf(stdout, ", \"ref_datetime\": \"%s\"", "GPS" ); // {"GPS", "UTC"} GPS-UTC=leap_sec
fprintf(stdout, ", \"ref_position\": \"%s\"", "MSL" ); // {"GPS", "MSL"} GPS=ellipsoid , MSL=geoid
#ifdef VER_JSN_STR
ver_jsn = VER_JSN_STR;
#endif
if (ver_jsn && *ver_jsn != '\0') fprintf(stdout, ", \"version\": \"%s\"", ver_jsn);
fprintf(stdout, " }\n");
}
}
if (out) fprintf(stdout, "\n");
fflush(stdout);
}
}
return 0;
}
/* -------------------------------------------------------------------------- */
double complex F1sum = 0;
double complex F2sum = 0;
int main(int argc, char *argv[]) {
FILE *fp;
char *fpname;
unsigned int sample_count;
int i;
int bit = 8, bit0 = 8;
int pos = 0, pos0 = 0;
double pos_bit = 0;
int header_found = 0;
double bitlen; // sample_rate/BAUD_RATE
int len;
double f1, f2;
int n;
double t = 0.0;
double tn = 0.0;
double x = 0.0;
double x0 = 0.0;
double complex X0 = 0;
double complex X = 0;
double xbit = 0.0;
float s = 0.0;
int bitbuf[3];
int cfreq = -1;
fpname = argv[0];
++argv;
while ((*argv) && (!wavloaded)) {
if ( (strcmp(*argv, "-h") == 0) || (strcmp(*argv, "--help") == 0) ) {
fprintf(stderr, "%s [options] audio.wav\n", fpname);
fprintf(stderr, " options:\n");
fprintf(stderr, " -v, --verbose\n");
fprintf(stderr, " -r, --raw\n");
return 0;
}
else if ( (strcmp(*argv, "-v") == 0) || (strcmp(*argv, "--verbose") == 0) ) {
option_verbose = 1;
}
else if ( (strcmp(*argv, "-r") == 0) || (strcmp(*argv, "--raw") == 0) ) {
option_raw = 1;
}
else if ( (strcmp(*argv, "--rawbits") == 0) ) {
option_rawbits = 1;
}
else if ( (strcmp(*argv, "-b") == 0) ) {
option_b = 1;
}
else if ( (strcmp(*argv, "--json") == 0) ) {
option_json = 1;
}
else if ( (strcmp(*argv, "--jsn_cfq") == 0) ) {
int frq = -1; // center frequency / Hz
++argv;
if (*argv) frq = atoi(*argv); else return -1;
if (frq < 300000000) frq = -1;
cfreq = frq;
}
else {
fp = fopen(*argv, "rb");
if (fp == NULL) {
fprintf(stderr, "%s konnte nicht geoeffnet werden\n", *argv);
return -1;
}
wavloaded = 1;
}
++argv;
}
if (!wavloaded) fp = stdin;
gpx.jsn_freq = 0;
if (cfreq > 0) gpx.jsn_freq = (cfreq+500)/1000;
i = read_wav_header(fp);
if (i) {
fclose(fp);
return -1;
}
bitlen = sample_rate/(double)BAUD_RATE;
f1 = 2200.0; // bit0: 2200Hz
f2 = 1200.0; // bit1: 1200Hz
N = 2*bitlen + 0.5;
buffer = calloc( N+1, sizeof(float)); if (buffer == NULL) return -1;
ptr = -1; sample_count = -1;
while (f32read_sample(fp, &s) != EOF) {
ptr++; sample_count++;
if (ptr == N) ptr = 0;
buffer[ptr] = s;
n = bitlen;
t = sample_count / (double)sample_rate;
tn = (sample_count-n) / (double)sample_rate;
x = buffer[sample_count % N];
x0 = buffer[(sample_count - n + N) % N];
// f1
X0 = x0 * cexp(-tn*2*M_PI*f1*I); // alt
X = x * cexp(-t *2*M_PI*f1*I); // neu
F1sum += X - X0;
// f2
X0 = x0 * cexp(-tn*2*M_PI*f2*I); // alt
X = x * cexp(-t *2*M_PI*f2*I); // neu
F2sum += X - X0;
xbit = cabs(F2sum) - cabs(F1sum);
s = xbit / bitlen;
if ( s < 0 ) bit = 0; // 2200Hz
else bit = 1; // 1200Hz
bitbuf[sample_count % 3] = bit;
if (header_found && option_b)
{
if (sample_count - pos_bit > bitlen+bitlen/5 + 3)
{
int bitsum = bitbuf[0]+bitbuf[1]+bitbuf[2];
if (bitsum > 1.5) bit = 1; else bit = 0;
bitframe[bitpos] = bit;
bitpos++;
if (bitpos >= LEN_BITFRAME-200) { // LEN_GPSePTU*BITS+40
print_frame(bitpos/BITS);
bitpos = 0;
header_found = 0;
}
pos_bit += bitlen;
}
}
else
{
if (bit != bit0) {
pos0 = pos;
pos = sample_count; //sample_count-(N-1)/2
len = (pos-pos0)/bitlen + 0.5;
for (i = 0; i < len; i++) {
inc_bufpos();
buf[bufpos] = 0x30 + bit0;
if (!header_found) {
if (compare() >= HEADLEN) {
header_found = 1;
bitpos = 10;
pos_bit = pos;
if (option_b) {
bitframe[bitpos] = bit;
bitpos++;
}
}
}
else {
bitframe[bitpos] = bit0;
bitpos++;
if (bitpos >= LEN_BITFRAME-200) { // LEN_GPSePTU*BITS+40
print_frame(bitpos/BITS);
bitpos = 0;
header_found = 0;
}
}
}
bit0 = bit;
}
}
}
fprintf(stdout, "\n");
if (buffer) { free(buffer); buffer = NULL; }
fclose(fp);
return 0;
}